The present invention relates to rims for land vehicles and, in particular, it relates to a tire rim having an emergency grooved internal annular support member which, when the tire is deflated, permits the vehicle to keep running with the annular support member supporting the deflated tire. The present invention relates also to a special tire construction whose interior surface is structurally arranged and adapted to engage the annular support member and be supported thereby.
Several prior art devices or structures are known that enable a vehicle such as a car, pick-up truck, motorbike, moped, or other wheeled vehicle to continue running when one tire or more is deflated and to permit the vehicle to proceed to a suitable location to replace the deflated tire.
However, many of these prior art devices are either very complex in construction, expensive to manufacture, or they affect the conformation or external aspect of the tire rim in such a way that requires that the device include parts which project from the rim, making a generally unaesthetic rim device. Accordingly, such devices have found limited commercial acceptance.
For example, GB Patent 960323, GB Patent 967397 and FR Patent 1408477 disclose devices for spare rims which are mechanically complicated and expensive to manufacture and maintain. Other devices, such as the rim devices disclosed in U.S. Pat. Nos. 2,019,120 and 3,208,798 disclose rim devices which include one or two externally mounted side support steel ring members attached to the rim, such that upon tire deflation, the supporting rings engage the ground surface to provide support for the wheeled vehicle.
Other tire support devices are found in U.S. Pat. No. 5,000,518 which relates to an annular ring attached to the rim and having an elastomer mounted to the end thereof, U.S. Pat. No. 1,766,393 which has an annular ring with a wedging groove having an annular elastomer thereon attached to the rim, and U.S. Pat. Nos. 2,203,774, 2,354,444 and 2,670,994 all which have grooved peripheral annular devices attached to the rim that retain the elastomer to the extended end of the annular device to engage the road surface during the run-flat condition. Argentinean Patent Application No. P010101027 also refers to a spare rim to be permanently used next to the main rim.
Japanese Patent PCT/JP93/00600 discloses a rim with internal central emergency support, in which the central support has interrupted or reduced peripheral continuity. Therefore, in case of the run-flat condition, the support contact against the internal tire band is discontinuous, a condition that will rapidly destroy the deflated tire during the run-flat condition.
Finally, EP Patent 0569710 and EP Patent 0490585 disclose two internal supports which are detachable and very complex because they consist of many parts. Furthermore, these internal supports lack a system with an entrance and exit passage to the groove for the tire. Another limitation of these devices is that the supports may only be mounted sideways with respect to the main rim.
One object of the present invention is an internal support run-flat member, preferably integrally mounted to the rim member, and having an annular groove therearound and a transverse passage divided into entrance and exit sections of the groove which permits mounting of a tire onto the rim member.
A further object of the present invention is an annular grooved internal support run flat member which provides reduced contact between the grooved run-flat member and the internal surface of the tire body thereby reducing the friction between the internal support member and the tire during the run-flat condition.
In the present invention, the annular grooved internal support member, having a transverse passage therethrough, includes an extended annular support contact surface where the divided transverse passage is positioned in the support member. Thus, when a vehicle runs with a deflated tire, the vehicle""s weight is more evenly distributed on the support member, thereby reducing wear of the rim and damage to the deflated tire. The annular groove may also serve as a mounting for an elastomer member to cushion the engagement between the support member and the inside surface of the deflated tire. Therefore, compared to a solid support, the weight of the tire rim is reduced without affecting the structural strength of the internal support member.
Additionally, the internal support member includes an annular groove therein having a transverse passage extending thereacross and divided into entrance and exit sections, thus maintaining and providing the continuity of the peripheral bearing surface for the internal support member. Therefore, in any rotational position of the rim, the support member provides a bearing surface for the deflated tire. This eliminates the necessity of placing padding or cushioning in transverse passages.
When the advantages of the present invention are combined with and added to the fact that the internal support member, when the wheel is assembled on the rim member, is positioned inside the mounted tire. Thus, the rim is not bulkier than conventional rim structures and has no parts which project outwardly from the rim. Because the support is positioned inside the tire, the external aspect of the tire mounted on the rim is not aesthetically affected.
Moreover, the rim member in accordance with the present invention does not require a complex mechanism which involves expensive manufacturing, maintenance, or repair costs, and the special tire construction of the present invention is complementary with the rim member and its internal support member, thereby preventing fractures or lateral shifts of the tire with respect to the rim during the run-flat condition. Finally, the increased thickness provided by the tread portion of the tire cushions running when a tire is deflated.